And with one sudden, violent thrust, Lauren pushed Dana down the stairs. Dana fell clumsily to the bottom, her descent muffled by the thick carpet. She let out one short scream that panicked Lauren. She froze. But she was committed now.

Dana lay completely still at the bottom of the stairs. Lauren had only moments before others might come running. She ran lightly down the staircase. At the bottom, she felt Dana’s pulse still beating in the soft curve of her throat. She grabbed a fistful of Dana’s shiny hair and pulled up her head and smashed it – as hard as she could, with all her rage – against the edge of the stair. Lauren’s heart was pounding violently. She looked up towards the top of the staircase, expecting someone to come at any moment; someone must have heard the scream. She was getting her story ready. But still no one came. She felt again for a pulse. Dana was dead. Glancing around, certain that no one had seen her, but not wanting to run into anyone who might have heard something, Lauren ran quietly along the back hall and made her way up the back staircase to the second floor and let herself back into her room. Ian was sound asleep.

She’d killed her. She’d killed Dani, the one person who knew what she’d done all those years ago, and all she felt was relief. And to know that she killed her before she could marry a rich man and have everything she ever wanted was especially satisfying.

They would think Dana fell down the stairs.

Lauren crawled back into bed and lay awake all night thinking about what she’d done. She felt no remorse.

But as the long night wore on, she started to worry. It had all happened so fast. She worried that Dana might have already said something to Matthew about her, that they might be able to tell it wasn’t an accident, that Dana wasn’t really dead.

Finally, she rose very early in the morning – having not slept at all – and crept downstairs before anyone else. She went quietly, careful to wake no one. Her heart was pounding as if it had grown to fill her entire chest. She stood on the landing at the top of the stairs and looked with cold relief down at Dana, so clearly dead. She swept down the stairs and bent over her, and confirmed that she was dead as a stone. She was so relieved she almost laughed.

And then she let out her unholy scream. People came running then, and she made sure they found her feeling for a pulse, in case the police found traces of her touch. She hoped it looked like an accident. And if anyone thought it didn’t, there was Matthew – the obvious suspect. She thought she was in the clear.

But then David, the attorney, had suggested that it wasn’t an accident at all, that it was murder. Still, she thought she might be all right. She thought they might think Matthew did it. And even if they didn’t, there was nothing to pin it on her. She was certain they wouldn’t find the connection between her and Dani.

But then after lunch she found the note in her book. The book she’d left in the lobby after breakfast. She took the book back upstairs with her after lunch and opened it and saw the small slip of paper inside, not folded, with her bookmark. And written on it, in big block capitals, in an obvious attempt to disguise the handwriting, was: I saw what you did to Dana.

She felt her heart jump in her chest like someone had jolted it with electricity. Someone had seen her! The note was unsigned. But she’d seen Candice in the lobby with the book in her hand, and she’d put it back down in a hurry. It had to be her. Was she going to try to blackmail her? Lauren thought uneasily about the hotel, how someone could have been hidden, behind a chair, in an alcove, how she might have been seen, or heard, after all. How rash she had been, how cocky, to take a quick glance around and assume that no one had been there! But Candice had been watching. She must have been. And now Candice was going to try to blackmail her. The bitch. But Lauren was not the kind of person to be blackmailed.

She knew what she had to do. It didn’t bother her to kill. Not if it was necessary. She’s always been able to do whatever is necessary. She’s different from other people. She’s always known this, ever since she was a little girl.

She has also known the importance of hiding such a fact. And she’s been clever enough not to have been discovered. It gives her a certain freedom that other people seem to lack. She can do things that they can’t. But she’s learned how to hide it by watching what other people do and pretending to be like them.

After finding the note, she told Ian she wanted a bit of time to herself and went to the small sitting room on the second floor with her book. She knew she couldn’t confront Candice in the library – it was too risky. Candice would probably come up to her room at some point. She’d already noticed that Candice had been wearing a silk scarf around her neck that morning.

After a while, she heard a sound in the hall. She got up from her seat by the window where the light was good enough to read, and moved quietly to the door and looked out. It was Candice, unlocking the door to her room across the hall. Candice opened the door and went inside, leaving the door open. Lauren crept down the corridor towards the open door. She looked quickly up and down the hall; no one was there. Candice was standing at the desk, her back turned to her. Lauren wasn’t going to negotiate. There was only one way to deal with a blackmailer. It was easy to sneak up behind Candice, her feet sinking noiselessly into the carpet. She quickly grabbed both ends of the scarf around Candice’s neck and pulled with all her strength. She didn’t let go until she was sure. She let Candice slump to the floor. Once Lauren was absolutely certain she was dead, she left, using her sleeve to close the door behind her. And then she retraced her steps to the sitting room, where she took up her book again.

Problem solved.

And then she had another idea. Checking that no one was coming, she slipped across the corridor and, picking the lock – a skill she’d learned as a troubled teenager – slipped quietly into the empty room at the end of the hall across from Gwen and Riley’s room. She had to be very quiet, so that they didn’t hear her. She messed up the bed a bit, made it look like it had been slept in. She went into the bathroom, and taking a towel, turned on the tap and sprinkled some water on the sink. Then she slipped carefully out of the room and returned to the sitting room feeling rather clever. She was sure no one had seen her this time.

She thought it would end there.

When Candice’s body was discovered, she found it easy to dissimulate, to pretend a horror, a fear, she did not feel. She behaved like the others, mirroring their emotions like a chameleon. She’s been doing this all her life. It was easy.

They’d all crowded around Candice’s room, messing up the murder scene. She deliberately bent down over Candice and made a show of touching her in front of everyone, trying to loosen the scarf, just in case. So she wouldn’t have to worry about trace evidence.

But by then she’d already realized that she’d made a terrible mistake.

It was when they’d returned from the icehouse, before Candice’s body had even been discovered. Bradley had gone off to the library to look for her. Lauren had stood in front of the reception desk and reached across, using her iPhone to search for a pen. She wanted to do a crossword by the light of the oil lamp. Her eyes fell on a small white notepad with paper the same size as the disturbing note in her book. She held the light closer. She could see the faint imprint of block letters. Even upside down, she could make out the words saw and Dana, clearly enough.